Federal Aviation Administration
FAA resets Airbus helicopter operators' gearbox check schedule
The FAA keeps the same main gearbox inspections and installation limits in place, but fixes the interval compliance times after finding errors in the earlier order. The updated rule takes effect July 14, 2026.
Airbus Helicopters operators in the United States will need to work to a corrected maintenance clock starting July 14, 2026. The FAA is superseding an earlier airworthiness directive for certain AS350, AS355 and EC130 models, but the safety checks themselves do not change.
- Takes effect July 14, 2026
- Covers AS350, AS355 and EC130 variants
- Keeps gearbox inspections and installation limits
- Corrects the maintenance intervals from the earlier directive
- Airbus Helicopters operators in the United States will follow a corrected maintenance schedule for certain AS350, AS355 and EC130 models starting July 14, 2026
Airbus Helicopters operators in the United States will follow a corrected maintenance schedule for certain AS350, AS355 and EC130 models starting July 14, 2026. The Federal Aviation Administration is superseding airworthiness directive 2025-06-04 for those helicopters, keeping the same inspections of the main gearbox, or MGB, and the same limits on installing an affected unit.
The change is about timing, not a retreat from the underlying safety order. FAA said the earlier directive had errors in the interval compliance times, so the new rule fixes the clock mechanics maintenance crews use while leaving the inspection and corrective-action requirements in place.
Why the gearbox checks stay
The directive covers AS350B, AS350B1, AS350B2, AS350B3, AS350BA, AS350D, AS355E, AS355F, AS355F1, AS355F2, AS355N, AS355NP, EC130B4 and EC130T2 helicopters. The concern is particles in the main gearbox, which can signal a problem that needs attention before it grows into a loss-of-control risk.
That is why the rule still requires repetitive inspections of the MGB bevel wheel and the MGB magnetic plug for particles, plus corrective action when needed. It also keeps the ban on installing an affected main gearbox unless the required conditions are met.
What operators need to update
For mechanics, owners and pilots who rely on these aircraft, the practical task is making sure the revised intervals are built into maintenance planning. The FAA estimates the rule affects 522 helicopters on the U.S. registry.
The agency says the new action does not add an extra economic burden beyond the existing inspections and follow-up work. It is a correction to the timetable, but the compliance burden on the hangar floor remains very real: the same checks, on the right schedule, to keep the aircraft airworthy.